microsoft/qlib · error · KeyError

Unknown meta keyword

Error message

Unknown meta keyword

What it means

Error "Unknown meta keyword" thrown in microsoft/qlib.

Source

Thrown at qlib/data/cache.py:235

    @staticmethod
    def reset_lock():
        r = get_redis_connection()
        redis_lock.reset_all(r)

    @staticmethod
    def visit(cache_path: Union[str, Path]):
        # FIXME: Because read_lock was canceled when reading the cache, multiple processes may have read and write exceptions here
        try:
            cache_path = Path(cache_path)
            meta_path = cache_path.with_suffix(".meta")
            with meta_path.open("rb") as f:
                d = restricted_pickle_load(f)
            with meta_path.open("wb") as f:
                try:
                    d["meta"]["last_visit"] = str(time.time())
                    d["meta"]["visits"] = d["meta"]["visits"] + 1
                except KeyError as key_e:
                    raise KeyError("Unknown meta keyword") from key_e
                pickle.dump(d, f, protocol=C.dump_protocol_version)
        except Exception as e:
            get_module_logger("CacheUtils").warning(f"visit {cache_path} cache error: {e}")

    @staticmethod
    def acquire(lock, lock_name):
        try:
            lock.acquire()
        except redis_lock.AlreadyAcquired as lock_acquired:
            raise QlibCacheException(
                f"""It sees the key(lock:{repr(lock_name)[1:-1]}-wlock) of the redis lock has existed in your redis db now.
                    You can use the following command to clear your redis keys and rerun your commands:
                    $ redis-cli
                    > select {C.redis_task_db}
                    > del "lock:{repr(lock_name)[1:-1]}-wlock"
                    > quit
                    If the issue is not resolved, use "keys *" to find if multiple keys exist. If so, try using "flushall" to clear all the keys.
                """

View on GitHub (pinned to 79633dd950)

Solutions

1. Remove the unknown keyword from the cache meta call; only supported meta keywords are accepted.
2. Check the spelling of the meta keyword against the cache API documentation.

When it happens

Trigger: This error is raised at qlib/data/cache.py:235 when the guard condition fails: "Unknown meta keyword". It triggers when the code path receives input or a state that violates the precondition checked at this point — e.g. an unimplemented abstract method being called, an unsupported argument type/value, or an invalid configuration. To avoid it, satisfy the documented precondition before this call: implement the required method in your subclass, or pass a supported value of the expected type as described by the message.

Common situations: See trigger scenarios.

AI-assisted analysis of microsoft/qlib@79633dd950 (2026-08-15). Data as JSON: /api/errors/5ea9a091a79e143a. Report an issue: GitHub.